Nondiffusing 1-phenyl-5-pyrazolone couplers for color photography



Patented Mar. 2, 1948 NONDIFFUSING' 1-PHENYL-5-PYRAZOLONE COUPLERS FOR COLOR PHOTOGRAPHY.

Walter Zeh, Wolfen, Kreis Bitterfeld, and Wilhelm Schneider and Alfred Friihlich, Dessau, Germany, assignors to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application February 17, 1942, Se-

rial No. 431,263. In Germany August 8, 1940 '1 Ulaims. (01'. 95-6) Our present invention relates to the production of color photographic images and more particularly to an improved photographic silver halide emulsion containing a dyestuff former.

In the productionof color photographic images by color forming development it is already known to use dyestuff formers containing radicals producing fastness to difiusion and groups making the compounds soluble in Water. For the production of red color tones it has, for instance, been proposed to use l-phenyl-E-pyrazolones having radicals preventing diffusion and ulfo or carboxyl groups. Such pyrazolone is, for instance, 1- (phenyl-3'-sulfonic acid) -3-heptadecyl-5-pyrazclone which would be especially suitable for highsensitive multi-layer materials owing to its high sensitivity if it did not show certain disadvantages. The high color yield of this dyestuff former i attended with a strong tendency to bronze" the color tone and a certain tendency to produce 2 stituted compounds so that the resulting multicolor images exhibit a red tint well graduated.

The phenylpyrazolones of the present invention contain in the 3-position ofthe pyrazolone nucleus radicals preventing diffusion, for instance, carbon chains with at least 6 carbon atoms color fogging. :Furthermore, this dyestuif comfication following hereinafter.

. These objects are accomplished by usin a 1- phenyl-5pyrazolone carrying a radical'producing fastness to difiusion in the 3-position of the pyrazolone nucleus and one or several substituents in the 3-, 4- or 5-positions of the phenyl radical besides groups increasing the solubility in water.

(see U. S. P. 2,186,349, dated January 9, 1940) or other radicals, for instance, those described in Stenger-Staude, Fortchritte der Photographic, volume II, 1940, pages 393-397. Besides these substituents groups rendering the components soluble in water may also be present in the phenyl nucleus such as sulfo, carboxyl or hydroxyl groups.

The silver halide emulsion prepared by means of the dyestufi components of the present invention may be cast to form single layers or worked up int'o'a multi-layer material containing further emulsion layers with dyestuff formers for the other component-colorsand, if necessary, filter layers, intermediate layers and anti-halation layers The emulsion layers may contain corresponding sensitizers and be arranged on one or both sides of the support. The multi-layer material may also comprise emulsion layers capable of producing dyestuffs according to a color photographic'method' rather than that mentioned above, The color images may be obtained by a Useful substituents are alkyl, alkoxy, alkthio,

alkseleno, aryloxy, and halogens. The pyrazolones are prepared by reacting phenylhydrazinesulfonic acids or phenylhydrazine carboxylic'acids correspondingly substituted with high-molecular weight acylacetic acid esters. The pyrazolones simple development'or a reversal development as negatives or positives respectively.

, .The following examples illustrate the present invention but they are not intended to limit it thereto. .I

Example l 10 g. of 1-(4'-methylphenyl-3'-sulfonic acid) 3-heptadecyl) -5-pyrazolone are neutralized with a diluted sodium hydroxide solution with. warming. The resulting solution of the sodium salt is substituted according to the invention are dismadeup to 200 cc. with water, then added to 1 kilo of a silver halide gelatin emulsion and finally cast. After exposure a non-bronzing slightly bluishred dyestuff image having an absorption maximum at about 530 m is produced by treating with a developer of the following composition:

Potassium carbonate grams '7 5 p-Dimethyla minoaniline sulfate do 2.5 Potassium bromide do 2.5 I Sodium sulfite dc 2.5

Water cc 1,000

and subsequently removing the formed silver.

Example 2 10 g. of the sodium salt of 1-(4'-brompheny1- 3-sulfonic acid) -3-heptadecyl-5-pyrazolone are dissolved in 200 cc. of water with gentle heating and added to 1 kilo of a silver halide gelatin emulsion layer before casting. On color forming development with a developer containing p-dimethylaminoaniline one obtains a non-bronzing, clear 7 and slightly bluish red dyestufi image. This dyestuif shows a maximum absorption of about 530 m Example 3 Example 4 10 g. of the sodium salt of 1-(4-chlorphenyl-3- carboxylic acid) -3-heptadecy1-5pyrazolone are dissolved in 200 cc. of water with warming and added to 1 kilo of a silver halide emulsion before casting. The color forming development with a developer containing p-dimethylaminoaniline yields a red .dyestufi image having a maximum absorption at about 540 m Example 5 g. of '1-(4-methoxyphenyl-3'-sulfonic acid) 3-heptadecyl5-pyrazolone are neutralized with a diluted sodium hydroxide solution and dissolved While gentlyheating. The solution made up to 200 cc. with water is added to a molten silver halide gelatin emulsion whereupon the emulsion is cast to form alayer. The color forming development yields a non-bronzing blue-red image the dyestufi of which has an absorption maximum of about 528 m Example 6 10 g. of 1 (4' meththiophenyl 3 sulfonic acid) -3-heptadecyl-5-pyrazolone are added to 1 kilo of a silver halide gelatin emulsion-and cast according to Example 5. One obtains a blue-red image the dyestufi of which shows an absorption 7 maximum of about 530' ma on color forming development with p-dimethylaminoaniline.

Example 7 10 g. of 1-(4-phenoxyphenyl-3-sulfonic acid) 3-heptadecyl-5-pyrazolone are neutralized with 30 cc. of a n/10 sodium hydroxide solution, dissolved with gentle heating, made up to 200 cc. and added to one kilo of a molten silver halide gelatin emulsion before casting. The exposed emulsion layer yields a blue-red dyestufi image having an absorption maximum of about 530 m on color forming development with a developer containing dimethylaminoaniline.

Example 8 If instead of the dyestuff former mentioned in Example '7 1-(4-phenoxyphenyl-3-sulfonic acid) 3 heptadecenyl 5 pyrazolone is used, a blue-red dyestuff image having a maximum absorption of 530 m is produced.

Example 9 10 g. of 1-(3-chloro-4'-methylphenyl-5'-sulionic acid) -3-heptadecyl-5-pyrazolone is neutralized with a diluted sodium hydroxide solution. The clear solution obtained by heating is made up to 200 cc. with water, added to 1 kilo of a molten silver halide gelatin emulsion and cast. A blue-red very transparent dyestuff image having an absorption maximum of about 535 m is obtained by the treatment with a developer containing dimethylaminoaniline.

Instead of the sodium salts of the pyrazolones of the invention other soluble salts may also be used,.especially alkali metal salts.

We claim:

1. A silver halide emulsion for color forming development containing as the dyestuff former for red a soluble salt of 1-phenyl-5-pyrazolone containing in the 3-position of the pyrazolone nucleus a radical producing fastness to difiusion and in the phenyl nucleus at least one group increasing the solubility in Water and in the positions of said phenyl nucleus selected from the group consisting of the 3-, 4- and 5- positions at least one substituent selected from the class consisting of alkyl, alkoxy, alkthio, alkseleno, aryloxy and halogens.

2. A silver halide emulsion for color forming development containing as the dyestuff former for red a soluble salt of 1-phenyl-5-pyrazolone containing in the 3 position of the pyrazolone nucleus a carbon chain having at least 6 carbon atoms and in the phenyl nucleus at least one group increasing the solubility in water and in the positions of said phenylnucleus selected from the group consisting of the 3-, 4- and 5-positions at least one substituent selected from the class consisting of alkyl, alkoxy, alkthio, alkseleno, a-ryloxy and halogens.

3. A silver halide emulsion for color forming development containing asthe dyestuff former for red a Water-soluble salt of 1-(4-methylphenyl-3'-sulf0nic acid) -3-heptadecyl-5-pyrazolone.

4. A silver halide emulsion for color forming development containing as the dyestufi former for red a soluble salt of 1(4-bromophenyl=-3- sulfonic acid) -3-heptadecyl-5-pyrazolone.

5. A silver halide emulsion for color forming development containing as the dyestuff former for red a soluble salt of 1-( l-chlorphenyl3'-carboxylic acid) -3-heptadecyl-5-pyrazolone.

6. A silver halide emulsion for color forming development containing as the dyestuif former for red a soluble salt of a 1-phenyl-5-pyrazolone containing in the 3-position of the pyrazolone nucleus a radical imparting iastness to diffusion in the binding agent of the silver halide emulsion and containing in the phenyl nucleus a group increasing the solubility of the compound in Water and in only one of the positions of said phenyl nucleus selected from the group consisting of the 3-, 4- and 5-positions a substituent selected from the class consisting of alkyl, alkoxy, alkthio, alkseleno, aryloxy and halogen.

'l. A silver halide emulsion as defined in claim 2 wherein the substituent in the 3-position of said pyrazolone is an aliphatic carbon chain of at least 6 carbon atoms and said substituent is directly linked to the carbon atom of the pyrazolone in said 3-position.

WALTER ZEH, \VILHELM SCHNEIDER.

ALFRED FRoHLIon.

(References on following page) 5 REFERENCES CITED f g? The following references are of record in the 2:200:30 file of this patent: 2,213,986

UNITED STATES PATENTS 5 Number Name Date Number 2,179,239 Wilmanns et a1. Nov. 7, 1939 836,144

Name Date Wilmanns et a1. Jan. 9, 1940 Schneider et a1. May 14, 1940 Kendall et a1. Sept. 10, 1940 FOREIGN PATENTS Country Date France Oct. 10, 1938 

